Developed by Bill James, God of Sabermatricians. The Pythagorean Theorem of Baseball states that a ball club's winning percentage should be equal to the square of the number of runs scored over the sum of the square of the number of runs scored and runs allowed.
(runs scored)2
Winning% = ----------------------------------
(runs scored)2 + (runs allowed)2
The theory is that in baseball, the greater the run differential while maintaining low scores is, the more likely a team is to win. Experiementally it's found that the Pythagorean Theorem of Baseball is more accurate if the exponent is around 1.83 rather than 2.
The Pythagorean Theorem of Baseball has led others to find similar predictive formulae in other sports like football, basketball and hockey.